The objective of this proposal is to test the hypothesis that E. coli kidney infections result in local and sometimes systemic immune responses which are detrimental to the mother and developing fetus. We have observed that obstetrical patients with E. coli kidney infections who have high levels of antibody in their urines against their own infecting E. coli may also have high levels of cross-reactive antibodies against antigen preparations of normal kidney, muscle, and placenta. The significance of these anti-kidney, anti-muscle, and anti-placenta antibodies to the mother and fetus are not known. One goal of this proposal is to identify and characterize these cross-reactive antibodies and immunogenically similar antigens through isotope-labelling, polyacrylamide gel electrohporesis, isoelectric focusing, and monoclonal antibody techniques. Cross-reactive antibodies and shared antigens, purified by these techniques, will be used as epidemiologic tools in studies of human urinary infections during pregnancy. Mothers with elevated levels of anti-E. coli, anti-tissue antibodies will be identified; whether or not such antibodies are present in the cord blood, amniotic fluid, or serum and urine of the newborn can be determined. Serologic findings will be correlated with outcome of pregnancy. An animal model will be necessary to show, more directly, the significance of such cross-reactive antibodies. We will attempt to demonstrate an autoimmune-type of pathogenesis through he passive transfer of these antibodies from donor rats with pyelonephritis to normal but pregnant recipient rats. Since an active infectious process may be important, a model of retrograde pyelonephritis in pregnant rats will be investigated; pathogenesis associated with tissue-bound antibody with reactivity for the infecting E. coli, would be indicative of an adverse role for these cross-reactive antibodies.